Lack of direct association between serum transferrin and serum biochemical indicators of vitamin A nutriture.

The association between serum transferrin and serum biochemical indicators of vitamin A and protein nutriture was investigated in 295 preschool children. Their levels of retinol and RBP correlated positively and significantly with transferrin, iron, total iron binding capacity (TIBC), total proteins and albumin. However, when removing those cases having unacceptable levels of total proteins (less than or equal to 6.4 g/dl) and/or albumin (less than or equal to 3.5 g/dl), the significant correlation between retinol (or RBP) and transferrin disappeared. It is concluded that transferrin levels are not directly related to the vitamin A nutritional status. The significance of this observation in relation to the known interaction between vitamin A and iron is discussed.